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Monique Reyrolle

Publications and source records attributed to Monique Reyrolle.

6 recordsLinked to original sources
PubMed2006

Integrated real-time PCR for detection and monitoring of Legionella pneumophila in water systems.

We evaluated a ready-to-use real-time quantitative Legionella pneumophila PCR assay system by testing 136 hot-water-system samples collected from 55 sites as well as 49 cooling tower samples collected from 20 different sites, in parallel with the standard culture method. The PCR assay was reproducible and suitable for routine quantification of L. pneumophila. An acceptable correlation between PCR and culture results was obtained for sanitary hot-water samples but not for cooling tower samples. We also monitored the same L. pneumophila-contaminated cooling tower for 13 months by analyzing 104 serial samples. The culture and PCR results were extremely variable over time, but the curves were similar. The differences between the PCR and culture results did not change over time and were not affected by regular biocide treatment. This ready-to-use PCR assay for L. pneumophila quantification could permit more timely disinfection of cooling towers.

Air Conditioning↗
PubMed2006

Characterization of the Legionella anisa population structure by pulsed-field gel electrophoresis.

We analysed 38 French isolates of Legionella anisa by means of pulsed-field gel electrophoresis (PFGE) with single or double digestion. Double digestion was more discriminatory than single digestion, and can thus be useful for epidemiological studies of L. anisa. Several isolates from different parts of France clustered together on the basis of their PFGE patterns (similarity cutoff of 80%), suggesting that the L. anisa population structure is homogenous or that a few clones of L. anisa strains have spread widely in France.

Electrophoresis, Gel, Pulsed-Field↗
PubMed2006

Quantitative real-time Legionella PCR for environmental water samples: data interpretation.

Quantitative Legionella PCRs targeting the 16S rRNA gene (specific for the genus Legionella) and the mip gene (specific for the species Legionella pneumophila) were applied to a total of 223 hot water system samples (131 in one laboratory and 92 in another laboratory) and 37 cooling tower samples (all in the same laboratory). The PCR results were compared with those of conventional culture. 16S rRNA gene PCR results were nonquantifiable for 2.8% of cooling tower samples and up to 39.1% of hot water system samples, and this was highly predictive of Legionella CFU counts below 250/liter. PCR cutoff values for identifying hot water system samples containing >10(3) CFU/liter legionellae were determined separately in each laboratory. The cutoffs differed widely between the laboratories and had sensitivities from 87.7 to 92.9% and specificities from 77.3 to 96.5%. The best specificity was obtained with mip PCR. PCR cutoffs could not be determined for cooling tower samples, as the results were highly variable and often high for culture-negative samples. Thus, quantitative Legionella PCR appears to be applicable to samples from hot water systems, but the positivity cutoff has to be determined in each laboratory.

Air Conditioning↗
PubMed2004

Clinical and environmental distributions of Legionella strains in France are different.

In France, the clinical distribution of Legionella species and serogroups does not correspond to their environmental distribution. Legionella pneumophila serogroup 1 is more prevalent among clinical isolates (95.4%) than in the environment (28.2%), whereas L. anisa is more frequent in the environment (13.8%) than in the clinical setting (0.8%).

France↗
PubMed2002

Identification of Legionella species by ribotyping and other molecular methods.

There are currently more than 40 species of Legionella and the identification of most of them by standard methods is often technically difficult. The aim of this study was to use a ribotyping method with endonuclease HindIII and a probe consisting of a set of five oligonucleotides (referred to as OligoMix5). A total of 123 strains, including 78 type or reference strains corresponding to 44 species, eight clinical and 37 environmental isolates were tested. The usefulness of the method was demonstrated for the identification at the species level of all of the 123 Legionella isolates tested, with each species showing a specific profile. Among the 15 serogroups of Legionella pneumophila, eight patterns were obtained. For the 45 field strains, the randomly amplified polymorphic DNA (RAPD) technique and intergenic 16S-23S ribosomal spacer PCR analysis (ITS 16-23S) were also used. Altogether, these three methods allowed the identification of all of strains tested. However, ribotyping has proven to be more effective than the other methods.

Environmental Microbiology↗